Diagnostic status and symptomatic behavior of hard-to-manage preschool children in middle childhood and early adolescence.

Followed 2 cohorts of hard-to-manage preschool children and comparison children without early problems to middle childhood and early adolescence. Children with early problems, especially problems that were still evident at school entry, were more likely to meet diagnostic criteria for an externalizing diagnosis at follow-up. Hard-to-manage children in Cohort 1 with problems that persisted from ages 3 through 9 years were much more likely to meet diagnostic criteria at age 13 than children whose early problems were less stable in elementary school. Similarly, hard-to-manage boys in Cohort 2 whose problems persisted at age 6 were more likely to meet criteria for an externalizing diagnosis at age 9 than hard-to-manage boys whose problems appeared less stable at age 6. Across cohorts, children with persistent problems had higher levels of symptoms and more varied symptoms at ages 3 and 4 and over the course of development.